A day after the manager had moved to play down reports of a rift with skipper John Terry, he saw the England defender lead his side to a 2-0 victory at npower Championship Middlesbrough and a place in the last eight.

The Blues took the lead when midfielder Ramires' 51st-minute shot flicked Fernando Torres, who knew little or nothing about it, and flew past keeper Jason Steele before the impressive Victor Moses made sure with a close-range finish 15 minutes from time.

But the European champions were made to work hard for their victory as Boro largely contained them before the break to give the locals among a crowd of 27,856 at the Riverside Stadium hope of a shock result.

However, a much-changed Chelsea gradually eased through the gears to ensure their progression and keep the prospect of a trophy at the end of the season on the horizon.

Benitez made no fewer than eight changes to the side which lost 2-0 at Manchester City at the weekend, with only keeper Petr Cech, defender Branislav Ivanovic and midfielder Ramires surviving, and that meant a return for Terry and a first senior start for 18-year-old Dutchman Nathan Ake.

However, as opposite number Tony Mowbray predicted, he still fielded a side packed with internationals and one capable of doing real damage.

But in the event, Chelsea turned in a tepid first-half display despite starting brightly enough with the pace and power of Moses down the right and the invention of Oscar causing problems for the Teessiders.

Oscar's eighth-minute cross was just too strong for Moses and Torres was similarly over-eager two minutes later as he attempted to pick out Yossi Benayoun in the middle.

But it took an important block by Nicky Bailey to deny Oscar with 12 minutes gone after Moses had exploded past full-back George Friend and squared for the Brazilian to shoot.

Chelsea were enjoying plenty of possession as Ake provided the fulcrum in the middle of the field, but with #50million striker Torres becalmed in a sea of indecision - he scuffed a 21st-minute shot tamely at Steele - they struggled to create clear-cut chances.

Mowbray had admitted in advance his side simply could not afford to go toe-to-toe with Chelsea, but having safely negotiated a difficult opening period, they started to make an impression themselves.

With Rhys Williams probing from central midfield and Muzzy Carayol and Faris Haroun providing the width, the Blues found themselves having to take a step backwards and might have conceded the opening goal with 26 minutes gone.

Striker Scott McDonald met Bailey's driven cross with a powerful header, but saw the ball fly wide of the far post with Cech looking on anxiously.

Carayol dragged an ambitious 36th-minute effort well wide, but he forced Cech into a less than convincing save with five minutes of the half remaining when his shot reared up off the turf and hit the keeper in the chest before being bundled to safety.

There were boos from the travelling fans at half-time, but the same 11 men emerged after the break as Benitez gave them further time to make their mark.

It took them only six minutes to do just that as they finally edged their way in front.

Oscar's determined run to the by-line and floated cross caused problems for the home defence and when Benayoun fed the loose ball out to Ramires, he curled the ball into the top corner with the help of a slight deflection off the unwitting Torres.

The Spaniard appeared to claim the goal as his team-mates celebrated, but there would have been no question over the shot he unleashed after beating the offside trap had Steele not got his fingertips to it.

Boro needed to re-group as they set about the task of trying to drag themselves back into the game, but with the visitors having settled into a rhythm, they were seeing too little of the ball to do a great deal about it.

Substitute Eden Hazard might have extended his side's lead with 18 minutes remaining with a deft shot which just evaded the top corner, but it was he who accepted Oscar's pass seconds later to provide Moses with a tap-in.

Cech had to be on his toes to keep out an 82nd-minute free-kick from Merouane Zemmama, and fellow substitutes Seb Hines and Ishmael Miller both went close in a late flurry, but Chelsea made it to the final whistle with their clean sheet intact.